Hydrocarbon conversion catalyst

ABSTRACT

A hydrocarbon conversion catalyst suitable for converion of heavy hydrocarbon oils containing large amounts of metallic contaminants, such as petroleum residua, to lower boiling products comprises a porous inorganic oxide such as bulk alumina composited with an inorganic oxide gel matrix such as silica-alumina, and a crystalline aluminosilicate zeolite.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a division of application Ser. No. 001,722, filed Jan. 8, 1979which is a continuation-in-part of U.S. application Ser. No. 746,188filed Nov. 30, 1976, which is a continuation-in-part of U.S. applicationSer. No. 626,225 filed Oct. 28, 1975 both abandoned, the teachings ofboth of which are hereby incorporated by specific reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel hydrocarbon conversion catalysts,methods for their preparation and uses thereof in hydrocarbon conversionprocesses. More particularly, the present invention relates to acatalytic cracking catalyst suitable for the conversion of high metalscontent hydrocarbon feeds.

2. Description of the Prior Art

Conventional hydrocarbon conversion catalysts are known to becomerapidly deactivated by contact with hydrocarbon feeds containing largeamounts of metallic contaminants. Typical feeds utilized, for example,in catalytic cracking have been gas oils, evenn though conversion ofheavy petroleum crude oils and residual oils would increase the yield ofgasoline obtainable from a barrel of oil. The heavy crude oils andresidual oils, such as bottoms from atmospheric or vacuum distillationof crude oil contain large amounts of material having atmosphericpressure boiling points above 1050° F.+ and contain relatively largeamounts of metallic contaminants generally present as organometalliccompounds, large amounts of nondistillable asphaltenes, i.e. pentane orheptane-insoluble material, large amounts of sulfur and nitrogen and ahigh Conradson carbon residue. The actual amounts of these materialswill vary according to the source of the crude and cut point made duringthe crude distillation. Tar sand oils, shale oils and liquified retortedcoal present similar processing difficulties. To facilitate the totalrefining of these heavy hydrocarbon oils, they may be subjected to ahydrogen refining process. Although the hydrogen refining stepfacilitates handling and further processing operations since it mayremove some of the metals, sulfur, nitrogen and polar compounds, it doesnot significantly affect the asphaltenes and the Conradson carbonresidue contents. Consequently, the hydrogen refined heavy crudes andresidua still contain large amounts of materials which are normallydeleterious to conventional cracking catalysts. The deposition of metalson the catalyst, principally nickel, vanadium and iron is particularlydisadvantageous since these metals adsorb on or near active catalyticsites and act as catalytic agents to produce hydrogen, methane and cokeinstead of the desired more valuable products such as gasoline and lightolefins.

It has now been found that the deleterious effect of feed metaldeposition on the hydrocarbon conversion catalyst can be minimized witha catalyst comprising as one component an adsorbent having specifiedsurface area and pore volume distribution composited with an inorganicoxide gel as second component. The catalyst also contains a crystallinealuminosilicate zeolite component.

Hydrocarbon conversion catalysts comprising a zeolite dispersed in asiliceous matrix are known, see, for example, U.S. Pat. No. 3,140,249and U.S. Pat. No. 3,352,796. Cracking catalysts containing a zeolite,silica-alumina and clay are also known, see, for example, U.S. Pat. No.3,449,265. Hydrocarbon conversion catalysts comprising a physicalmixture of silica-alumina and a crystalline aluminosilicate zeolite in asiliceous matrix are also known, see, for example, U.S. Pat. No.3,558,476. Processes for preparing hydrocarbon conversion catalystscontaining a zeolite, clay, and silica or silica alumina are disclosedin U.S. Pat. Nos. 3,867,308 and 3,867,310.

SUMMARY OF THE INVENTION

In accordance with the invention there is provided a process for theconversion of a hydrocarbon oil which comprises: contacting said oil athydrocarbon conversion conditions with a catalyst comprising (1) acrystalline aluminosilicate zeolite, (2) a catalytic inorganic oxidegel, and (3) a porous inorganic oxide having a surface area greater thanabout 200 square meters per gram and having at least 0.2 cubiccentimeter per gram of its pore volume in pores ranging in diameter fromabout 90 to about 200 angstroms, said catalyst having at least 0.4 cubiccentimeter per gram of its pore volume in pores greater than 90angstroms in diameter.

In accordance with the invention there is further provided the novelhydrocarbon conversion catalyst utilized in the above-stated process anda process for preparing the catalyst which comprises: (a) blending aslurry of an inorganic oxide hydrogel with a slurry of a porousinorganic oxide; (b) removing at least a portion of the liquid from theresulting mixture; (c) drying the mixture resulting from step (b) toproduce dried solids; (d) washing the dried solids resulting from step(c) with a washing medium; (e) separating the washed solids from saidwashing medium; (f) drying the separated solids resulting from step (e)to a moisture content ranging from about 8 to about 15 weight percent,and (g) recovering the catalyst of the present invention therefrom.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In general, the catalyst composition of the present invention willcomprise a crystalline aluminosilicate zeolite, and inorganic oxide geland a porous inorganic oxide.

Zeolite Component

The crystalline aluminosilicate zeolite may be chosen from any of theknown crystalline synthetic or naturally occurring zeolites. Examples ofthese zeolites include the zeolites designated by the Linde Division ofUnion Carbide Corporation by the letters X, Y, A, L (these zeolites aredescribed in U.S. Pat. Nos. 2,882,244; 3,130,007; 2,882,243 and BelgianPat. No. 575, 117, respectively), ZSM type zeolites, such as ZSM-5zeolite described in U.S. Pat. No. 3,702,866 and in Nature, vol. 272,Mar. 30, 1978, pp. 437-438, as well as the naturally occurringcrystalline zeolites such as faujasite, chabazite, erionite, mordenite,offretite, gmelinite, analcite, etc. The zeolite, as produced or foundin nature normally contains an alkali metal such as sodium and/orpotassium and/or an alkaline earth metal such as calcium and magnesium.The zeolites differ from each other in structure, composition andparticularly in the ratio of silica to alumina contained in the crystallattice structure. For use in hydrocarbon conversion processes, thehigher silica to alumina ratios among isostructural zeolites arepreferred because of their higher stability at elevated temperature,particularly in the presence of steam. Therefore, whereas the zeolitecomponent of the present invention may be any of the above-statedzeolites, the zeolites having silica to alumina ratios above 3 will bepreferred. This includes natural and synthetic faujasite and mordenite.Typical among these zeolites is the synthetic faujasite variety whereinthe silica to alumina rtion is about 2.3 to 7, preferably 3 to 6, morepreferably 4.5 to 5.5. A high silica to alumina ratio zeolite is zeoliteY. Type X zeolite wherein the silica to alumina ratio is less than 3,e.g. 2.5 may also be used to advantage, although the most preferredzeolite components for use in the catalyst of the present invention willbe those having a silica to alumina ratio greater than 3. Thecrystalline zeolites have uniform pore openings ranging in diameter from3 to 15 angstroms. The preferred pore size catalyst for use as a zeolitecomponent in the present invention will be zeolites having uniform poresize diameter ranging from about 6 to about 15 angstroms. For use as ahydrocarbon conversion catalyst component, it is usually necessary toreduce the alkali metal content of the crystalline aluminosilicatezeolite to a content of less than 10 weight percent, preferably lessthan 6 weight percent, and more preferably less than about 1 weightpercent since the alkali metal components are normally undesirablecatalytic components for the desired hydrocarbon conversion reactions.The alkali metal content reduction may be accomplished as is well knownin the art by exchange with any one or more of the cations selected fromGroup IB through Group VIII metals of the Periodic Table of Elements(the Periodic Table referred to herein is given in the Handbook ofChemistry and Physics published by the Chemical Rubber PublishingCompany, Cleveland, Ohio, 45th Edition, 1964), as well as hydrogencation or precursors (i.e. NH₄ ⁺) capable of conversion to hydrogencation. The preferred cations are those selected from the groupconsisting of rare earth metals, calcium, magnesium and hydrogen ormixtures thereof.

Suitable amounts of the zeolite component will range from about 1 to 40,preferably from about 5 to 40, more preferably from about 8 to 35 weightpercent based on the total catalyst.

Inorganic Oxide Gel Component

Inorganic oxide gel suitable as component of the catalyst of the presentinvention are amorphous catalytic inorganic oxides such as silica,alumina, silica-alumina, silica-zirconia, silica-magnesia,alumina-boria, alumina-titania, and the like, and mixtures thereof.Preferably the inorganic oxide gel is a silica-containing gel, morepreferably the inorganic oxide gel is an amorphous silica-aluminacomponent such as a conventional silica-alumina cracking catalyst,several types and compositions of which are commercially available.These materials are generally prepared as a cogel of silica and aluminaor as alumina precipitated on a preformed and pre-aged hydrogel. Ingeneral, silica is present as the major component in the catalyticsolids present in such gels, being present in amounts ranging betweenabout 55 and 100 weight percent, preferably the silica will be presentin amounts ranging from about 70 to about 90 weight percent.Particularly preferred are two cogels, one comprising about 75 weightpercent silica and 25 weight percent alumina and the other comprisingabout 87 weight percent silica and 13 weight percent alumina. Theinorganic oxide gel component may suitably be present in the catalyst ofthe present invention in an amount ranging from about 45 to about 98weight percent, preferably from about 45 to about 90 weight percent,more preferably from about 45 to about 82 weight percent based on thetotal catalyst.

The Porous Inorganic Oxide

The porous inorganic oxide may suitably be present in the total catalystin amounts ranging from about 1 to about 55, preferably from about 5 to45, more preferably from about 10 to 30 weight percent based on thetotal catalyst. The porous inorganic oxide may be chosen from a widevariety of inorganic oxides having the required physicalcharacteristics. Preferably the porous inorganic oxide is a materialhaving initially in itself prior to being composited less catalyticactivity than the inorganic oxide gel component of the catalyst. It mayalso be chosen from porous inorganic oxides which have substantially nocatalytic activity for conversion prior to being composited with theother components. Preferably, the porous inorganic oxide will be a bulkmaterial. The term "bulk" with reference to the porous inorganic oxideis intended herein to designate a material which has been preformed andplaced in a physical form such that its surface area and pore structureis stabilized so that when it is added to an impure inorganic gelcontaining considerable amounts of residual soluble salts, the saltswill not alter the surface and pore characteristics measurably nor willthey promote chemical attack on the preformed porous inorganic oxidewhich could then undergo change. For example, addition of "bulk" aluminawill mean a material which has been formed by suitable chemicalreaction, the slurry aged, filtered, dried, washed free of residualsalts and then heated to reduce its volatile contents to less than about15 weight percent. The resulting porous inorganic oxide is suitable foruse as the porous component of the present invention. Suitable materialsfor use as porous inorganic oxide in the catalyst of the presentinvention include alumina, titania, silica, zirconia, magnesia andmixtures thereof. Preferably the porous inorganic oxide is a bulkalumina. Any type of alumina is suitable provided that it has thephysical characteristics required by the present invention.

The porous inorganic oxide initially used as component in the catalystof the present invention, after heating at 1000° F. in air for sixhours, will have a surface area of at least about 200 m² /g. The porousinorganic oxide must have at least 0.2 cubic centimeter per gram of itspore volume in pores having diameters ranging from about 90 to about 200angstroms. It should be noted that the abovestated physicalcharacteristics of the porous inorganic oxide are those of the porousinorganic oxide prior to being composited with the other components. Thefinished total catalyst of the present invention will have a pore sizedistribution such that when the pore volume is measured after subjectingthe finished catalyst to steam treatment at 1400° F., 0 psig, for 16hours, it will have at least 0.4 cubic centimeter per gram of its porevolume in pores having diameters greater than 90 angstroms. The porevolume referred to herein is determined by nitrogen adsorption (BETmethod).

The catalysts of the present invention may be prepared by any one ofseveral methods. A preferred method of preparing one of the catalysts ofthe present invention, that is, a catalyst comprising silica-alumina andporous alumina, is to react sodium silicate with a solution of aluminumsulfate to form a silica/alumina hydrogel slurry which is then aged togive the desired pore properties, filtered to remove a considerableamount of the extraneous and undesired sodium and sulfate ions and thenreslurried in water. Separately, a bulk alumina is made, for example, byrecting solutions of sodium aluminate and aluminum sulfate, undersuitable conditions, aging the slurry to give the desired poreproperties of the alumina, filtering, drying, reslurrying in water toremove sodium and sulfate ions and drying to reduce volatile mattercontent to less than 15 weight percent. The alumina is then slurried inwater and blended, in proper amount, with the slurry of impuresilica/alumina hydrogel.

The zeolite component is added to this blend. A sufficient amount ofeach component is utilized to give the desired final composition. Theresulting mixture is then filtered to remove a portion of the remainingextraneous soluble salts therefrom. The filtered mixture is then driedto produce dried solids. The dried solids are subsequently reslurried inwater and washed substantially free of the undesired soluble salts. Thecatalyst is then dried to a residual water content of less than about 15weight percent. The catalyst is recovered after calcination for 6 hoursat 1000° F. in air. When this catalyst is tested after subjecting it tosteam treatment for 16 hours at 0 psig and 1400° F., it will have atleast 0.4 cc/g of its pore volume in pores having diameters greater than90 angstroms to be suitable as catalyst of the present invention.

The catalyst of the present invention is suitable for hydrocarbonconversion processes such as catalytic cracking, hydrocracking,isomerization, alkylation, and other carbonium ion catalyzed reactiontypes.

It is particularly suited for use in a catalytic cracking processes andit is especially suited for catalytic cracking of high boiling pointhydrocarbonaceous feeds having high metals content, a high Conradsoncarbn residue, high sulfur content, high nitrogen and other polarmolecules.

Catalytic cracking with a catalyst of the present invention can beconducted in any conventional catalytic cracking manner. Suitablecatalytic cracking conditions include a temperature from about 700° F.to about 1200° F. and a pressure ranging from about subatmospheric toseveral hundreds of atmospheres, typically from about atmospheric to 100psig.

The process may be carried out in a fixed bed, moving bed, ebullientbed, slurry, transferline or a fluidized bed operation.

Although the catalysts of the present invention can be used to convertany of the conventional hydrocarbon feeds used in a given process (thatis, it can be used to crack heavy naphthas and gas oils), they areespecially suitable for feeds containing a high content of metalcontaminants. By way of example, the catalyst of the present inventioncan be used to convert heavy crude oils, and residual oils such aspetroleum atmospheric or vacuum distillation tower bottoms. The residualoils may contain 95 to 99 weight percent or more of the nickel andvanadium content of the crude oil feed. For example, the total metalscontent of such oils may range up to 2,000 weight ppm or more and thesulfur content may range up to 8 weight percent or more. The API gravityof such feeds may range from about 5° API to about 35° API and theConradson carbon residue of the heavy feeds will generally range fromabout 5 to about 50 weight percent (as to Conradson carbon residue, seeASTM test D-189-65) although the catalyst can be used to convert lowerConradson carbon feeds.

The following examples are presented to illustrate the invention.

EXAMPLE 1

Comparative catalytic cracking experiments were performed utilizing ahydrotreated Cold Lake Whole Crude oil feed, at the followingconditions: 950° F., 0 psig for 2 minutes at a space velocity of 15W/Hr/W to determine the conversion to 430° F. minus boiling materials.The properties of the feed include: 19.4° API gravity; 0.406% sulfur;0.151% nitrogen; 5.22% Conradson carbon; 2.5% asphaltenes; 4.9 ppmnickel and 7.2 ppm vanadium. Distillation of the feed showed only 70.7%boiling below 1050° F. at atmospheric pressure. The results aresummarized in Table I.

The preparations and compositions of catalysts A through K aresummarized in Table II.

As can be seen from Table I, the catalysts of the present invention,that is, catalyst A to D', in which the inert absorbent used had atleast 0.2 cc/g of its pore volume in pores having diameters ranging fromabout 90 to 200 angstroms and wherein the steamed finished catalyst hadat least 0.4 cc/g of its pore volume in pores greater than 90 angstroms,showed superior conversion results relative to the other catalyststested that did not have the required physical characteristics.

                                      TABLE I                                     __________________________________________________________________________               Surface Prop. of Adsorbent                                                         Pore Vol.     Steamed.sup.(1)                                            Surface                                                                            in 90-200 A   Catalyst                                             Wt. % Area,                                                                              Diameter Pores,                                                                             PV (>90 A dia),                                                                        Conv., wt. %                           Catalyst                                                                           Adsorbent                                                                           m.sup.2 /g                                                                         cc/g     % RE-Y                                                                             cc/g     (15 W/Hr/W)                            __________________________________________________________________________    A    29    393  1.09     11   0.773    76.2                                   B    44    393  1.09     11   0.610    73.7                                   C    30    393  1.09     11   0.692    72.9                                   D    29    393  1.09     11   0.577    70.4                                   D'   29    523  0.21     11   0.760    69.2                                   E    28    309   0.024   11   0.365    59.6                                   F    30    328  0.16     12   0.352    66.7                                   G    29    528  0.18     11   0.910    62.6                                   H    None  --   --       8.5  0.430    57.8                                   I    40    ˜13                                                                          0.01     16   0.258    55.7                                   J    29     85  0.09     11   0.397    57.5                                   K    29     14  0.01     11   0.524    63.8                                   __________________________________________________________________________     .sup.(1) Steamed 16 hours at 1400° F. and 0 psig                  

                  TABLE II                                                        ______________________________________                                        Cat-                                                                          alyst  Catalyst Preparation Details                                           ______________________________________                                        A    Sodium silicate solution gelled by adding alumi-                              num sulfate solution. Aged 1 hour at 90° F. pH                         adjusted to 5.2. Filtered. Reslurried and                                     blended with Conoco HP grade alumina and calcined                             rare earth exchanged faujasite (Y-type). Spray                                dried. Washed. Dried. Composition: 11%                                        Faujasite/29% HP grade alumina/60% (85% SiO.sub.2 /15%                        Al.sub.2 O.sub.3) Gel.                                                   B    Made the same as A. Composition: 11% Faujasite/                               44% HP grade alumina/45% (85% SiO.sub.2 /15% Al.sub.2 O.sub.3) Gel.      C    Sodium silicate solution gelled by adding dilute                              H.sub.2 SO.sub.4 to pH 10.5. Then add sodium aluminate                        solution to pH 12.0. Age 1 hour at 115° F. Then                        add aluminum sulfate solution to pH 4.3. Adjust                               pH to 6.8. Filter. Reslurried and blended with                                Conoco HP grade alumina and calcined rare earth                               exchanged faujasite (Y-type). Spray dried.                                    Washed. Dried. Composition: 11% Faujasite/30%                                 HP grade alumina/59% (75% SiO.sub.2 /25% Al.sub.2 O.sub.3) Gel.          D    Sodium silicate solution gelled with dilute H.sub.2 SO.sub.4                  to pH 8. Aged 110 minutes at 110° F. Aluminum                          sulfate solution added. pH brought to 5.2.                                    Filtered. Reslurried and blended with Conoco HP                               grade alumina and calcined rare earth exchanged                               faujasite (Y-type). Spray dried. Washed. Dried.                               Composition: 11% Faujasite/29% HP grade alumina/                              60% (87% SiO.sub.2 /13% Al.sub.2 O.sub.3) Gel.                           D'   Sodium silicate solution gelled with CO.sub.2 at pH                           10.5. Aged 30 minutes at 98° F. Aluminum sulfate                       solution added to bring pH to 5.0. Filtered.                                  Reslurried and blended with Ketjen commercial                                 alumina and calcined rare earth exchanged fauja-                              site (Y-type). Spray dried. Washed. Dried.                                    Composition: 11% Faujasite/29% Ketjen alumina/                                60% (87% SiO.sub.2 /13% Al.sub.2 O.sub.3) Gel.                           E.   Sodium silicate solution gelled with dilute H.sub.2 SO.sub.4                  at pH 8.4. Aged 1 hour at 110° F. Aluminum sul-                        fate solution added and pH adjusted to 5.0.                                   Filtered. Reslurried and blended with a separate                              slurry of hydrous alumina (previously made by                                 reacting solutions of sodium aluminate and alumi-                             num sulfate) and calcined rare earth exchanged                                faujasite (Y-type). Spray dried. Washed. Dried.                               Composition: 11% faujasite/29% alumina/60% (85%                               SiO.sub.2 /15% Al.sub.2 O.sub.3) Gel.                                    F    Sodium silicate solution gelled with CO.sub.2 at pH                           10.5. Aged 30 minutes at 98° F. Aluminum sulfate                       Reslurried and blended with Conoco SB grade                                   alumina and calcined rare earth exchanged fauja-                              site (Y-type). Spray dried. Washed. Dried.                                    Composition: 12% faujasite/30% SB grade alumina/                              58% (87% SiO.sub.2 /13% Al.sub.2 O.sub.3) Gel.                           G    Sodium silicate solution gelled by adding alumi-                              num sulfate to pH 9.0. Aged 1 hour at 90° F.                           Then added more alum solution to pH 3.7. Adjusted                             pH to 5.0 with NH.sub.4 OH. Filtered. Reslurried and                          blended with Nalco commercial alumina and calcined                            rare earth exchanged faujasite (Y-type). Spray                                dried. Washed. Dried. Composition: 11% fauja-                                 site/29% Nalco alumina/60% (85% SiO.sub.2 /15% Al.sub.2 O.sub.3)              Gel.                                                                     H    Sodium silicate solution gelled by adding CO.sub.2 to                         pH 10.5. Aged 30 minutes at 98° F. Aluminum                            sulfate solution added to bring pH to 5.0 and                                 then calcined rare earth exchanged faujasite (Y-                              type) blended therein. Filtered. Reslurried.                                  Spray dried. Washed. Dried. Composition: 8.5%                                 faujasite/91.5% (87% SiO.sub.2 /13% Al.sub.2 O.sub.3) Gel.               I    This catalyst is a commercial cracking catalyst.                              It is believed to contain about 16% rare earth                                faujasite (Y-type), about 40-45% kaolin, and                                  about 40-45% silica/alumina gel.                                         J    Sodium silicate solution gelled with dilute H.sub.2 SO.sub.4                  to pH 8.3. Aged 1 hour at 112° F. Aluminum sul-                        fate added to pH 3.9. pH adjusted to 5.2 with                                 NH.sub.4 OH. Filtered. Reslurried and blended with                            Florex (attapulgite clay from Floridin Co.) and                               calcined rare earth exchanged faujasite. Spray                                dried. Washed. Dried. Composition: 11% fauja-                                 site/29% attapulgite/60% (85% SiO.sub.2 /15% Al.sub.2 O.sub.3) Gel.      K    Sodium silicate solution gelled with aluminum sul-                            fate at pH 10.2. Aged 1 hour at 90° F. Additional                      alum added to bring pH to 4.5. Adjusted pH to                                 5.15 with NH.sub.4 OH. Filtered. Reslurried and                               blended with kaolin (hydrafine SD grade from J.                               Huber Corp.) and calcined rare earth exchanged                                faujasite (Y-type). Spray dried. Washed. Dried.                               Composition: 11% faujasite/29% kaolin/60% (85%                                SiO.sub.2 /15% Al.sub.2 O.sub.3) Gel.                                    ______________________________________                                    

EXAMPLE 2

A catalyst of the invention was made as follows: sodium silicatesolution was gelled with CO₂ at pH 10.5. After aging at 98° F. for 30minutes, aluminum sulfate was added to bring the pH to 5.0. Afterfiltering, the slurry was blended with Conoco HP grade alumina andcalcined rare earth exchanged faujasite, spray dried, washed andcalcined 16 hours at 1000° F. in air. This catalyst, designated "M"comprised 11% faujasite, 20% HP grade alumina, and 69% (75% SiO₂ /25%Al₂ O₃) gel.

Catalyst M and catalyst I of Table II were each steamed for 16 hours at1400° F. and 0 psig and charged to a cyclic fluid bed unit operating at950° F. reactor temperature and about 1250° F. regenerator temperature.The feed was a Santa Barbara 650° F.⁺ atmospheric residua having 13.5°API gravity, 1.68 wt. % sulfur, 0.26 wt. % basic nitrogen, 10.34%Conradson carbon, 103.1 ppm nickel, and 116.5 ppm vanadium. The metalsdeposited on each catalyst were allowed to build up to 3000 ppmequivalent Ni (ppm Ni+0.2 ppm V). At this metals level, the crackingperformances of the two catalysts were compared. This is shown in TableIII, listing the activity, carbon yield, and H₂ production of catalyst Mrelative to catalyst I of Table II:

                  TABLE III                                                       ______________________________________                                        Catalyst          I           M                                               ______________________________________                                        Relative Activity 1.00        2.04                                            Relative Carbon   1.00        0.33                                            Relative H.sub.2  1.00        0.78                                            ______________________________________                                    

The data of Table III show the superior performance of catalyst M, whichis a catalyst in accordance with the present invention. Not only is theactivity of catalyst M, which comprised only about 11% faujasite, aboutdouble the activity of conventional commercial catalyst I, whichcomprised about 16% faujasite, but catalyst M was less responsive to theadverse effects of nickel and vanadium, as shown by the much lowercarbon and hydrogen yields.

EXAMPLE 3

A catalyst of the invention was made as follows: Sodium silicatesolution was gelled with CO₂ at pH 10.5. After aging at 98° F. for 30minutes, aluminum sulfate was added to bring the pH to 5.0. Afterfiltering, the slurry was blended with a slurry of Conoco HP alumina andNafaujasite (Linde SK-30 grade). The combined slurry was colloid milled,spray dried, and washed to remove extraneous soluble salts. The filtercake was reslurried in hot H₂ O (130° F.) and rare earth chloridesolution added and stirred for 30 minutes. The slurry was filtered,rinsed, and dried. The catalyst comprises about 16% faujasite/29% HPalumina/55% silica-alumina gel. Rare earth content of the total catalystis 2.7 weight percent as RE₂ O₃. This catalyst is designated hereincatalyst "N".

EXAMPLE 4

Another catalyst of the invention was made using the same procedure asin Example 3. After washing the catalyst it was reslurried in diluterare earth chloride solution at 130° F. for 30 minutes, filtered, rinsedwith H₂ O and dried. This catalyst, designated "P" comprises about 25%faujasite/29% HP alumina/46% silica-alumina gel. Rare earth content ofthe total catalyst is 4.2 weight percent as RE₂ O₃.

EXAMPLE 5

The catalyst of this example is also a catalyst of the invention. It wasmade by the same procedure as outlined in Example 3. After washing, thewet filter cake was reslurried in a dilute rare earth chloride solutionat 130° F. for 30 minutes, filtered, rinsed with H₂ O, and dried. Thiscatalyst, designated "Q" comprises about 35% faujasite/25% Hpalumina/40% silica-alumina gel. Rare earth content of the total catalystis 5.4 weight percent as RE₂ O₃.

EXAMPLE 6

Catalyst I, which is the catalyst of reference, and catalysts N, P and Qwere steamed at 1400° F. for 16 hours and 0 psig. Comparative crackingexperiments were performed utilizing a hydrotreated Cold Lake WholeCrude oil feed at 950° F. over a 2 minute process period. The oil feedis described in Example 1. In Table IV, the catalysts are compared at acommon 75% conversion level to 430° F- products.

                  TABLE IV                                                        ______________________________________                                        Catalyst     I        N        P      O                                       ______________________________________                                        % Faujasite  16-19    16       25     35                                      % Porous Inorganic                                                                         ˜40                                                                              29 Al.sub.2 O.sub.3                                                                    29 Al.sub.2 O.sub.3                                                                  25 Al.sub.2 O.sub.3                     Oxide        (Kaolin)                                                         At 75% Conversion:                                                            W/Hr/W        7.3      9.5     13.1   17.0                                    Carbon, %     9.9      8.0      7.6    8.0                                    C.sub.5 /430° F., wt. %                                                             55.2     57.3     58.3   56.0                                    430/650° F., wt. %                                                                  19.0     20.1     19.3   19.2                                    ______________________________________                                    

The data show that catalyst N at the same approximate faujasite contentas catalyst I showed higher activity and improved product distribution.Increasing the zeolite content of the catalyst to 25 to 35 weightpercent as in catalysts P and Q served principally to increase activitywithout adverse effects on product distribution.

What is claimed is:
 1. A catalyst comprising: (1) a crystallinealuminosilicate zeolite, (2) a catalytic inorganic oxide gel, and (3) aporous inorganic oxide initially having a surface area greater thanabout 200 square meters per gram and having at least 0.2 cubiccentimeter per gram of its pore volume in pores ranging in diameter fromabout 90 to about 200 angstroms, said catalyst having at least 0.4 cubiccentimeter per gram of its pore volume in pores greater than 90angstroms in diameter.
 2. The catalyst of claim 1 wherein said porousinorganic oxide is selected from the group consisting of alumina,silica, titania, zirconia, magnesia and mixtures thereof.
 3. Thecatalyst of claim 1 wherein said porous inorganic oxide is alumina. 4.The catalyst of claim 1 wherein said porous inorganic oxide is silica.5. The catalyst of claim 1 wherein said porous inorganic oxide comprisesfrom about 1 to about 55 weight percent of the total catalyst.
 6. Thecatalyst of claim 1 wherein said porous inorganic oxide comprises fromabout 5 to about 45 weight percent of the total catalyst.
 7. Thecatalyst of claim 1 wherein said porous inorganic oxide in itself hasless catalytic activity than said inorganic oxide gel component.
 8. Thecatalyst of claim 1 wherein said zeolite comprises from about 1 to about40 weight percent of the total catalyst and wherein said inorganic oxidegel comprises from about 45 to about 98 weight percent of the totalcatalyst.
 9. The catalyst of claim 1 wherein said inorganic oxide gel isa silica-containing gel.
 10. The catalyst of claim 1 wherein saidinorganic oxide gel is a cogel of silica-alumina.
 11. The catalyst ofclaim 1 wherein said crystalline aluminosilicate zeolite has thestructure of faujasite.
 12. The catalyst of claim 1 wherein saidcrystalline aluminosilicate zeolite has uniform pore diameters rangingfrom about 6 to about 15 angstroms and wherein the silica to aluminaratio is greater than
 3. 13. The catalyst of claim 1 wherein saidzeolite comprises less than 10 weight percent alkali-metal, calculatedas the metal.
 14. The catalyst of claim 1 wherein said porous inorganicoxide has been preformed and placed in physical form such that itssurface area and pore structure are stabilized.